In a CDMA receiving device a cell search operation is performed for establishing synchronicity with a base station, and in order to perform a hand over, a cell search operation is constantly performed also during communication. The cell search operation includes detection of scrambling code and frame timing, and SFN detection (for example, refer to Patent Document 1).
In the SFN detection, SFN can be detected from decoded data of a broadcast channel. Determination of whether a decoded data result is correct or not is performed by a decoded CRC (Cyclic Redundancy Check) code.
In the abovementioned SFN detecting method, as shown in FIG. 6, in each frame, decoding processing is performed from physical data of 2 frames, and a CRC (Cyclic Redundancy Check) judgment is carried out.
At a point in time ((2) and (4) in FIG. 6) at which a CRC determination result at a consecutive TTI (Transmission Time Interval) is OK, an SFN is extracted from BCH (Broadcast Channel) decoded data (in this case, SFN=n+2, SFN=n+4) and a determination of an SFN detection success is made. In other words, the SFN is extracted from the BCH decoded data by a one-time CRC determination of being OK, and a determination of the SFN detection success is made.
[Patent Document 1]
JP Patent Kokai Publication No. JP-P2003-179954